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    <title>ShellCheck: SC3008 – In POSIX sh, select loops are undefined.</title>
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    <h1>SC3008 – ShellCheck Wiki</h1>
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    <h2 id="in-posix-sh-select-loops-are-undefined">In POSIX sh, select
loops are undefined.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC3008.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="co">#!/bin/sh</span></span>
<span id="cb1-2"><a href="SC3008.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;Select file to show&quot;</span></span>
<span id="cb1-3"><a href="SC3008.html#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="cf">select</span> input <span class="kw">in</span> <span class="pp">*</span></span>
<span id="cb1-4"><a href="SC3008.html#cb1-4" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
<span id="cb1-5"><a href="SC3008.html#cb1-5" aria-hidden="true" tabindex="-1"></a>  <span class="fu">ls</span> <span class="at">-l</span> <span class="st">&quot;</span><span class="va">$input</span><span class="st">&quot;</span></span>
<span id="cb1-6"><a href="SC3008.html#cb1-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<p>Either switch to bash:</p>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC3008.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="co">#!/usr/bin/env bash</span></span>
<span id="cb2-2"><a href="SC3008.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;Select file to show&quot;</span></span>
<span id="cb2-3"><a href="SC3008.html#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="cf">select</span> input <span class="kw">in</span> <span class="pp">*</span></span>
<span id="cb2-4"><a href="SC3008.html#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
<span id="cb2-5"><a href="SC3008.html#cb2-5" aria-hidden="true" tabindex="-1"></a>  <span class="fu">ls</span> <span class="at">-l</span> <span class="st">&quot;</span><span class="va">$input</span><span class="st">&quot;</span></span>
<span id="cb2-6"><a href="SC3008.html#cb2-6" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span></code></pre></div>
<p>Or write your own menu.</p>
<h3 id="rationale">Rationale:</h3>
<p>Your script uses a shell feature not supported by the shebang. Either
rewrite the script to be portable, or change the shebang to explicitly
require a shell like Bash. There is no simple substitution for a
<code>select</code> loop, so either write your own using compatible
constructs like <code>for</code> loops, or switch to a shell that
supports them.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None</p>
<h3 id="related-resources">Related resources:</h3>
<ul>
<li>Help by adding links to BashFAQ, StackOverflow, man pages, POSIX,
etc!</li>
</ul>
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